Heat sinking devices may be coupled to a heat generating device, such as a power electronics device, to remove heat and lower the maximum operating temperature of the heat generating device. Cooling fluid may be used to receive heat generated by the heat generating device by convective thermal transfer, and remove such heat from the heat generating device. For example, a jet of cooling fluid may be directed such that it impinges a surface of the heat generating device. Another way to remove heat from a heat generating device is to couple the device to a finned heat sink made of a thermally conductive material, such as aluminum.
However, as power electronics are designed to operate at increased power levels and generate increased corresponding heat flux due to the demands of newly developed electrical systems, conventional heat sinks are unable to adequately remove the heat flux to effectively lower the operating temperature of the power electronics to acceptable temperature levels. Further, conventional heat sinks and cooling structures require additional bonding layers and thermal matching materials (e.g., bond layers, substrates, thermal interface materials). These additional layers add substantial thermal resistance to the overall assembly and make thermal management of the electronics system challenging. Moreover, semiconductor devices may have high on-resistance which generates more heat and reduces the performance of the devices.
Accordingly, a need exists for alternative power electronics assemblies and power electronics devices using a metallization of at least a portion of an exterior surface of a cooling structure to provide one or more electrical current flowpaths and enhance the performance of the devices.